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  1. JDK
  2. JDK-8114823

G1 doesn't honor request to disable class unloading

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    • b138
    • generic
    • generic
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        Class unloading should be disabled by -XX:-ClassUnloading (or the equivalent -Xnoclassgc). However, G1 does not honor such requests correctly.

        When G1 performs a full GC, it does not conditionalize the marking phase of root processing based on the ClassUnloading option. Instead it always marks the roots as if class unloading is enabled. Unfortunately, later code does attempt to honor ClassUnloading, with resulting problems.

        When G1 performs a concurrent mark, it conditionalizes some of the work on the ClassUnloadingWithConcurrentMark option, which defaults to true. That feature is not disabled when ClassUnloading is requested disabled, so it is presently possible to have ClassUnloading false and ClassUnloadingWithConcurrentMark true. As a result, later processing that is disabled when ClassUnloading is disabled may go awry.

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            backported by

            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-8208924 G1 doesn't honor request to disable class unloading

            • P2 - Crashes, loss of data, severe memory leak.
            • Resolved

            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-8216746 G1 doesn't honor request to disable class unloading

            • P2 - Crashes, loss of data, severe memory leak.
            • Resolved

            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-8206405 G1 doesn't honor request to disable class unloading

            • P2 - Crashes, loss of data, severe memory leak.
            • Closed
            relates to

            Bug - A problem which impairs or prevents the functions of the product. JDK-8085965 VM hangs in C2Compiler

            • P3 - Major loss of function.
            • Resolved

            Bug - A problem which impairs or prevents the functions of the product. JDK-8059128 VM hangs because threads fail to synchronize at safepoint

            • P2 - Crashes, loss of data, severe memory leak.
            • Closed

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                sjohanss Stefan Johansson
                kbarrett Kim Barrett
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